Fender rhodes pickups experiment

[Diggyfresh]

Hi guys! New member here! I discovered this great forum by the guys at diystomboxes.com!

I have a question thats been bothering me for awhile and probably the knowledgable peeps around here could help. :



I built a "Baby" rhodes using a chinese piano toy, the kind that has metal tines hit by a little wooden block.
the fact it has metal tines made me think pickups would work so i got some rhodes pickup from ebay for cheap.

The "thing" has 15 pickups, they have a dc resistance of about 170-190 Ohm each. I wired them in series-parallel mimicking how they are wired
in the rhodes. I used the info from this site : Steve's Corner - Pickup Maintenance & Replacement

i think i wired the first 7 in serie, parallel to the last 8 in serie. (7serie-parallel to 8 serie) I added a volume and tone pot exactly like in the rhode piano also. wich gives me a total Dc resistance of about 2.1 K Ohm, no idea about impedance.


The thing works when amplified by my mic preamp's DI input (Api 512c), but the problem i have is the volume is too low and doesn't interact well
with guitar stompboxes (probably an impedance issue..).


do any of you have any ideas on how i could optimize this setup so i could get a decent volume out of it ?

probably wire them in a different way?? remove the volume? i lack knowledge in that area.


Any help would be greatly appreciated,
Thank you very much!


(please forgive my grammar errors ect, french is my first language)

[David King]

Welcome Diggyfish,

The first question the jumps to mind is; "where are you placing the pickup relative to the tines?" Are they closest to the ends or the center where the movement will be the greatest? Are they mounted as close as possible to the tines without touching or dampening them? I'd suggest doubling them up in a push/pull series wiring and then wiring each note's pair in parallel or series to end up with a DCR of between 4 and 10k. If that doesn't work then try a stratoblaster preamp.

[Peter Naglitsch]

I have a genuine -78 or -79 Rhodes and even those instruments doesn't have a load of output. I run it through an high quality bass guitar preamp before sending the signal to a tube guitar amp for a bit of bite and a touch of tremolo. Now we have a real keyboard player so the piano both sound good and are being played well...

I also had the oportunity to play around with a few of those coils for a violin pickup (totaly customer specified, it sounded like crap...) and these are greate pickups, but only for what they are designed. They are made to pick up the signal from the end of a vibrating stiff metal rod, not the middle of a string or tines or similar. If you can snap some pictures of the assembly it migh be easier to se whats going on and find some possible improvements.

And you english is fine (said the Swede...)

[Diggyfresh]

Thanks alot peeps!!

The pickups are placed exactly like in the rhodes. right at the end of the metal rod, close as possible.
I should have said i also have an orginal Rhodes, the passive one without the amp, and i get a way greater signal and guitar pedals work great on it.
im pretty sure the problem probably lies in the way the pickups are connected to each other... or maybe i could try removing the tone and volume pots, although
i plugged it exactly like a rhode.


Thanks David, but im not sure i get what you saying? can you elaborate on the "push/pull series wiring"? I am not familiar with the way guitar pickups are wired.
Do you mean wire them in serie as pair and then each pair in parallel ? Keep in mind the pickups have a dcr of about 190 Ohm each.

i will investigate those "stratocaster preamps" for sure!

[Steve Conner]

Are the tines in this Chinese piano toy made of ferrous metal?

[David King]

You could have on shorted pickup that is affecting all the others?. Yes 190 ohms isn't much so putting them all in series makes more sense if you just have 24-36 keys.
You might also need to re-magnetize the magnets if they are old and have been bouncing around in a box for decades. Lots of info around here on magnetizing alnico.

A push/ pull scenario would mean having two pickups on opposite sides of the same tine but working together in unison i.e. in phase, that should double your output.

The Strato-Blaster is a simple FET (field-effect transistor) circuit that will boost the signal without loading down the pickups with too much input impedance. You can google it and find the parts list and schematic and possibly a kit as well.

[Diggyfresh]

@ Steve Conner i don't get your question ? yes i think they are, a magnet will stick to them.

And the tines are big and loud, so that isn't the issue.


@ David, Thanks alot man! yes, i should try wiring them serie, I have 15 notes. ok i understand your push-pull thing, unfortunately i only have 15 pickups
and not much room to do that anyways but it's a good idea!.

I hope i dont have to remagnetized them... haha..

So if i wire them in serie, i should have around 2850 Ohm DCR total.. i will try. and thanks again for the strat preamp, i'll build one!


BTW, i just measured the DCR of my original fender rhodes ( out the output jack) with 73 notes, a volume and tone pot : rougly 1600 Ohm.
and i get a decent volume in my D.I input.


any other ideas wouldbe appreciated! Thanks guys